Span<T>(Void*, Int32) points to original unmanaged block or copies it?

Doc is unclear - does Span<T>(Void*, Int32) refer to the original unmanaged memory block, or copy the unmanaged data into a T[] managed object, that is then pinned when a pinnable ref is requested?
The former would certainly be desired, at least in some instances, but from tests it seems impossible to get the address of the original unmanaged object when requesting a pinnable ref. Doc needs to be clear here.

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* ID: 12542bab-90d5-ee4f-fe42-3ad37dd133a1
* Version Independent ID: 1265f19b-bf12-ea32-0b5a-1bfae94b1be4
* Content: [Span<T> Constructor (System)](https://docs.microsoft.com/en-us/dotnet/api/system.span-1.-ctor?view=netcore-2.2#System_Span_1__ctor_System_Void__System_Int32_)
* Content Source: [xml/System/Span`1.xml](https://github.com/dotnet/dotnet-api-docs/blob/master/xml/System/Span`1.xml)
* Product: **dotnet-api**
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